Project Summary/Abstract Consumption of ?away-from-home? or prepared foods is rising and contributes to poor diet, obesity and related health problems. Prepared foods include ?ready-to-eat? food purchased outside the home at restaurants and other retail food stores. While most prepared foods are sold in restaurants, increasingly, supermarkets and other similar food retailers are offering these products. By April/May 2017, most chain food retailers in the United States began posting calories on restaurant menus and on prepared foods. These retailers did so in anticipation of coming federal regulations that will require calorie labeling. The regulations were initially set for implementation in May 2017 but were delayed until May 2018; by this date, all chain food retailers with 20 or more sites across the US will be required to label. This grant proposal will be the most comprehensive and objective examination of calorie labeling to date, covering different settings (fast-food restaurants, supermarkets) and potential effects of labeling (customer purchases, reformulation of food items, health outcomes, altered social norms). Conducted in partnership with a large fast-food chain franchisee in the South and a large supermarket chain in the Northeastern United States, we will examine transaction records from 93 fast-food restaurants and 194 supermarkets to determine whether calories purchased from prepared foods change after labeling. The research team also will track the nutrition characteristics of items sold at the largest US restaurant chains and at a supermarket chain to determine whether the food industry introduces new lower-calorie products after labeling or reformulates existing products to be lower calorie. We will incorporate all of these results on changes after labeling into a model that will predict whether obesity rates also change after labeling. Further, by examining mentions, searches and sentiment regarding calories, labeling, and food establishments on the internet and social media platforms, this study will have an unprecedented opportunity to determine whether calorie labeling has a broader societal effect, beyond purchasing and health outcomes. To date, all calorie labeling research has been conducted in restaurants, cafeterias, or lab settings. This study will be the one of the few to examine comprehensive transaction records from food retailers, the first to evaluate the effect of calorie labeling on supermarket prepared foods, and the first to examine the impact of a federal nutrition policy on internet and social media discussions regarding calories and labeling. Funding this research will lay the foundation for a number of exciting future research opportunities. This project will lead to the creation of a large dataset of transactions over time from restaurants and supermarkets and data from internet and social media platforms that could be used for evaluation of future policies, such as the US Food and Drug Administration?s forthcoming changes to the Nutrition Facts label. The partnership with a large fast-food chain franchisee and a large supermarket chain also may lead to real-world experiments of strategies to augment calorie labeling. This project will provide important answers to policymakers, industry leaders, and public health professionals about whether and how calorie labeling works.